User Guide

28
32.1 connection notes
The negative input and output connections are all common. The
mains earth should always be connected regardless of what
other equipment is used. This only grounds the case and the
electrostatic screen within the transformer, and is not connected
to the signal negative. In order to avoid hum loops, the signal
negative of the whole system should be connected to the mains
earth (ground) in one place. This should be the primary signal
source.
32.2 protection notes
If the amplifier’s external case reaches 70°C due to prolonged
running at high power, the mains supply will be interrupted and
the illuminated logo will switch off until the amplifier has cooled
down. This may take up to thirty minutes.
NAP 250
32 Installation and Operation
The NAP 250 should be installed in its final operating location before connecting cables
or switching on. Switch on the source and preamplifier components, with the volume
turned down, before switching on the NAP 250. The NAP 250 power button is located on
the front panel.
The NAP 250 is very heavy and care should be taken when lifting or moving it. Make
sure that the surface it is to be placed on can support the full weight.
OPERATION OF THE AMPLIFIER’S THERMAL PROTECTION
SUGGESTS PROLONGED USE AT TOO HIGH A VOLUME LEVEL.
YOUR LOUDSPEAKERS MAY BE AT RISK IF THIS IS THE CASE.
THE VOLUME SHOULD BE REDUCED.
32.3 loudspeaker cable and connectors
Only Naim Audio speaker cable should be used to connect a
loudspeaker to the output of the NAP 250. Custom Naim Audio
loudspeaker connectors are supplied to make the connection.
IN ORDER TO COMPLY WITH CURRENT EUROPEAN SAFETY
REGULATIONS IT IS ESSENTIAL THAT THESE ARE USED.
DAMAGE TO THE AMPLIFIER MAY RESULT IF “HIGH
DEFINITION” CABLE OR ANY OTHER SPECIAL CABLE IS USED
TO CONNECT THE LOUDSPEAKERS.
33 NAP 250 Rear
34 NAP 250 Specification
Power Output:
80 Watts per channel, 8Ω
400 VA Transient
Quiescent Consumption:
25VA
Voltage Gain:
+29dB
Input Impedance:
18kΩ
Frequency Response:
-3dB @ 2Hz and 65kHz
Dimensions (H x W x D):
87 x 432 x 314mm
Weight
15.8kg
Mains Supply:
100-120V or 220-240V, 50/60Hz
ch2
-ve
ch1
Input
mains input
and fuse
right
speaker
left
speaker
signal input
ch1 & ch2